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Aug 31, 2024 · Gymnosperm - Evolution, Paleobotany, Reproduction: Gymnosperms were the first seed plants to have evolved. The extinct Progymnospermophyta is thought to be ancestral to seed plants. The earliest recognized group of gymnospermous seed plants are of the extinct Pteridospermophyta (pteridosperms or seed ferns), which originated in the Devonian and were widespread by the Carboniferous.
Oct 31, 2023 · The name gymnosperm means “naked seed,” which is the major distinguishing factor between gymnosperms and angiosperms, the two distinct subgroups of seed plants. This term comes from the fact that the ovules and seeds of gymnosperms develop on the scales of cones rather than in enclosed chambers called ovaries.
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Angiosperms took over by the middle of the Cretaceous period (145.5–65.5 million years ago) in the late Mesozoic era, and have since become the most abundant plant group in most terrestrial biomes. The two innovative structures of pollen and seed allowed seed plants to break their dependence on water for reproduction and development of the ...
gymnosperm with one extant species, the Gingko biloba: a tree with fan-shaped leaves gnetophyte gymnosperm shrub with varied morphological features that produces vessel elements in its woody tissues; the phylum includes the genera Ephedra, Gnetum and Welwitschia gymnosperm seed plant with naked seeds (seeds exposed on modified leaves or in cones)
Gymnosperms are the seed-producing plants, but unlike angiosperms, they produce seeds without fruits. These plants develop on the surface of scales or leaves, or at the end of stalks forming a cone-like structure. Gymnosperms belong to kingdom ‘Plantae‘ and sub-kingdom ‘Embryophyta’. The fossil evidence suggested that they originated ...
Angiosperms and gymnosperms are the two major groups of vascular seed plants. Angiosperms, which are flowering plants, are the largest and most diverse group within the kingdom Plantae. With around 300,000 species, they represent approximately 80 percent of all the known green plants now living.
